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So Auralflea (Kevin) contacted me about restoring this Accuphase E-202 and i thought it would make a good thread about restorating a pretty fucked up amp back to its former glory.

Properly restoring an amplifier isn't just a case of recapping it and setting the offset and bias its much more involved:-

A complete recap

All zener diodes replaced

Any out of spec transistors or any that have known problems replaced

Any out of spec or stressed resistors replaced

Adjustment pots replaced with sealed multiturns

All boards defluxed and cleaned

All switches and pots cleaned with deoxit

All solder joints inspected anf resoldered if needed

Probably a couple more i can't think of at the mo.

This amp had been with another tech for around six months with an apparent switch fault, which he could'nt rectify. Seems that it had been with a 'tech' for a while i thought the rest (not the switch) would be in tiptop shape, how wrong was I, after further inspection i have found dozens of resistors with cracked insulation only a handful of original transistors and a couple of bodged amutuer repairs.

Starting to see things that arn't original, the most obvious being the RS rectifier which has replaced the original rectifier pcb. As you can see its been installed in a pain in the arse place and the pins on the big psu cap underneath have been bent to accomadate it, pretty shoddy soldering as well.

More worring soldering (Just tagged on the pins) on the circuit breaker.

Huge respect to Chris for taking this on - these are complicated amps with many hard-to-find components, and this is one job I refused (sorry Kevin) - looking at the issues you've found, I don't regret that decision one little bit! (sorry again Kevin! )

I'll watch this thread with interest! Best of luck

As I recall it, you declined the job before I even asked!! Not that I blame you at all, this looks to be a seriously time-consuming job ahead for Chris.

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The mouser order turned up, 112 different components some with multiples of the same.....

Never before have i had to change so much inside an amp but, this thing is so far gone needs must. Some compromises i have had to make are using radial caps (panasonic FC/FM) instead of axials as the quailty and performance is much better and using different resistors than i would normally (i usually use vishay rn's) simply because of the large number that need replacing.

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A quick update as now back off annual holiday, Psu regulator card has almost been completed just waiting on a few missing parts to turn up. As you can see only 3 original transistors have survived the hacked attemps of repair, the replacements have been replaced with correctly crossreferenced parts, also i dont know whats happening with the resistors in this amp but the enamel is shrinking/cracking on nearly all of them, poor quality maybe?

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The heatsinks are there just to see if it fires up, they are a replacement item someone's put in as it looks like (as I have found) good replacements for these transistors are the wrong orentation I.e the back of the transistors face the wrong way. And it's getting to be a twat to find replacement sinks